feat: add WordCount

strutil/string.go

@@ -329,3 +329,34 @@ func SplitWords(s string) []string {
 
 	return words
 }
+
+// WordCount return the number of meaningful word, word only contains alphabetic characters.
+// Play: todo
+func WordCount(s string) int {
+	var r rune
+	var size, count int
+
+	isWord := false
+
+	for len(s) > 0 {
+		r, size = utf8.DecodeRuneInString(s)
+
+		switch {
+		case isLetter(r):
+			if !isWord {
+				isWord = true
+				count++
+			}
+
+		case isWord && (r == '\'' || r == '-'):
+			// is word
+
+		default:
+			isWord = false
+		}
+
+		s = s[size:]
+	}
+
+	return count
+}

strutil/string_example_test.go

@@ -413,3 +413,28 @@ func ExampleSplitWords() {
 	// []
 	// []
 }
+
+func ExampleWordCount() {
+
+	result1 := WordCount("a word")
+	result2 := WordCount("I'am a programmer")
+	result3 := WordCount("Bonjour, je suis programmeur")
+	result4 := WordCount("a -b-c' 'd'e")
+	result5 := WordCount("你好，我是一名码农")
+	result6 := WordCount("こんにちは，私はプログラマーです")
+
+	fmt.Println(result1)
+	fmt.Println(result2)
+	fmt.Println(result3)
+	fmt.Println(result4)
+	fmt.Println(result5)
+	fmt.Println(result6)
+
+	// Output:
+	// 2
+	// 3
+	// 4
+	// 3
+	// 0
+	// 0
+}

strutil/string_test.go

@@ -325,3 +325,20 @@ func TestSplitWords(t *testing.T) {
 		assert.Equal(v, SplitWords(k))
 	}
 }
+
+func TestWordCount(t *testing.T) {
+	assert := internal.NewAssert(t, "TestSplitWords")
+
+	cases := map[string]int{
+		"a word":                       2, //   {"a", "word"},
+		"I'am a programmer":            3, //   {"I'am", "a", "programmer"},
+		"Bonjour, je suis programmeur": 4, // {"Bonjour", "je", "suis", "programmeur"},
+		"a -b-c' 'd'e":                 3, // {"a", "b-c'", "d'e"},
+		"你好，我是一名码农":                    0, // nil,
+		"こんにちは，私はプログラマーです": 0, // nil,
+	}
+
+	for k, v := range cases {
+		assert.Equal(v, WordCount(k))
+	}
+}